Byte Order Mark (BOM) is a very useful piece of data that often appears at the start of UTF ASCII/UC files, but it can be a bit of an annoyance if trying to send location HTTP headers on a PHP file for example, since a location header must be the very first part of a file that is output.
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Jamie Balfour
BSc (Hons) Computer Science, PGDE Computing
J. Balfour
Computer Scientist
Full Stack Developer
& Educator
Full Stack Developer
& Educator